The FBI made headlines last week when it announced that it had shut down the illegal online drug bazaar Silk Road and arrested its alleged operator Ross Ulbricht. According to the FBI’s complaint, the arrest led to the seizure of $3.6 million in bitcoins—the virtual currency Silk Road users employed to buy and sell illegal drugs online.

Though the FBI’s seizure was the second most valuable act of bitcoin confiscation ever, the Feds were actually unable to appropriate the vast majority of bitcoins associated with the Silk Road enterprise, Ulbricht’s personal stash. According to Forbes, roughly $80 million worth of bitcoins—the personal fortune Ulbricht amassed by running Silk Road—remains untouched by the government

So why can’t the FBI get its hands on the money? The reason has to do with the design of bitcoins themselves. A bitcoin cannot be transferred from one user to another without the first users “private key,” or password to verify the transaction. Unless Ulbricht hands over his password, the FBI will be unable take possession of the money. But can the government force Ulbricht to hand over a password? Is it conceivable that even if Ulbritch is convicted that the government could end up never seizing his riches?

According to Susan Brenner a professor of law and technology at the University of Dayton, Ulbricht could be protected by the fifth amendment from having to hand over the key to his wealth. The 5th amendment protects citizens from being forced to incriminate themselves, and producing a password that enables access to these coins could be construed as an act of self-incrimination. Brennan explains:

“In order to take the 5th Amendment privilege and refuse to produce something, the act of producing it must communicate that (i) it exists (which may seem obvious, but sometimes producing the thing says it exists), (ii) you have it (or have control over it) and (iii) this is the thing you were ordered to produce (authentication . . . i.e., this is my gun, my money, etc.). The Supreme Court has held that the act of producing something is NOT testimonial if the government knows all three things, i.e., if they all are a foregone conclusion.”

In other words, if the government already knows conclusively that the bitcoins are Ulbricht’s, then he will be unable to claim 5th amendment privilege. He must show that handing over the password somehow makes it evident that the bitcoins are his. Brennan continues:

“If I represented Ulbricht, I would argue that while the generic existence of the bitcoins is a foregone conclusion, his “possession” of them is not . . . and that by providing the password would conclusively establish that they belong to him, which would mean that he would, under the act of production as testimony standard, be “testifying” and, since the testimony would incriminate him, he could take the 5th Amendment.”

So what if Ulbricht is denied 5th amendment protection? Can the government ever actually force Ulbricht to give up his stash? Well, no, but Ulbricht can be held in contempt of court and held in jail indefinitely for defying its order. Then again, Ulbricht is accused of operating perhaps the most vast and far-reaching illegal drug operation in history, so he might be headed to jail for a very long time regardless of whether or not he decides to hand over his bitcoins.